Capacity control valve

Abstract

A capacity control valve includes a valve housing provided with a suction port through which a suction fluid of suction pressure Ps passes, and a control port through which a control fluid of control pressure Pc passes, a valve element configured to be driven by a solenoid, a spring that biases the valve element in a direction opposite to a driving direction of the solenoid, and a CS valve formed by a CS valve seat and the valve element, the CS valve being configured for opening and closing a communication between the control port and the suction port in accordance with a movement of the valve element. The capacity control valve further includes communication controller that controls a communication between the control port and a space on a back surface side of the valve element.

The invention claimed is: 
     
       1. A capacity control valve comprising:
 a valve housing provided with a suction port through which a suction fluid of suction pressure passes, and a control port through which a control fluid of control pressure passes; 
 a valve element configured to be driven by a solenoid; 
 a first spring that biases the valve element in a direction opposite to a driving direction of the solenoid; and 
 a control-suction valve formed by a control-suction valve seat provided on an inner peripheral surface of the valve housing and the valve element, the control-suction valve being configured for opening and closing a communication passage between the control port and the suction port by causing the valve element to separate from and come into contact with the control-suction valve seat, wherein 
 the control pressure is controlled in accordance with opening and closing operation of the control-suction valve, 
 a space configured for communicating with the control port is formed inside the valve housing and arranged on a back surface side of the valve element, 
 the valve element has a contact portion which is capable of coming into contact with the control-suction valve seat and which is housed in a valve chamber communicating with the suction port, 
 the valve chamber is formed by a single continuous space, 
 the control-suction valve seat is provided so as to face the valve chamber, 
 the control pressure of the control fluid acts on the valve element through the communication passage which provides a communication between the valve chamber and a control fluid supply chamber communicating with the control port, and 
 a supplemental spring is arranged in the control fluid supply chamber and interlockingly coupled to the valve element. 
 
     
     
       2. The capacity control valve according to  claim 1 , wherein
 the space on the back surface side of the valve element communicates with the suction port. 
 
     
     
       3. The capacity control valve according to  claim 2 , wherein
 the space on the back surface side of the valve element communicates with the suction port via a throttle. 
 
     
     
       4. The capacity control valve according to  claim 3 , wherein
 a guide hole through which the valve element is inserted is formed in the valve housing on the back surface side of the valve element with respect to the suction port. 
 
     
     
       5. The capacity control valve according to  claim 3 , wherein
 a communication between the control port and the space on the back surface side of the valve element is secured when an electromagnetic force is generated in the solenoid. 
 
     
     
       6. The capacity control valve according to  claim 5 , wherein
 the solenoid includes a coil, a plunger, a center post, and the first spring arranged between the plunger and the center post, 
 the plunger, the valve housing in which a through hole passing through in the axial direction is formed, and the center post, which is capable of closing an opening end of the through hole, cooperatively form a passage of the communication between the control port and the space on the back surface side of the valve element and 
 the center post is movable toward the plunger by the electromagnetic force generated in the solenoid. 
 
     
     
       7. The capacity control valve according to  claim 6 , wherein
 the center post is pushed onto the valve housing by a second spring, and 
 the second spring has larger bias force than the first spring. 
 
     
     
       8. The capacity control valve according to  claim 2 , wherein
 a communication between the control port and the space on the back surface side of the valve element is secured when an electromagnetic force is generated in the solenoid. 
 
     
     
       9. The capacity control valve according to  claim 8 , wherein
 the solenoid includes a coil, a plunger, a center post, and the first spring arranged between the plunger and the center post, 
 the plunger, the valve housing in which a through hole passing through in the axial direction is formed, and the center post, which is capable of closing an opening end of the through hole, cooperatively form a passage of the communication between the control port and the first space on the back surface side of the valve element, and 
 the center post is movable toward the plunger by the electromagnetic force generated in the solenoid. 
 
     
     
       10. The capacity control valve according to  claim 9 , wherein
 the center post is pushed onto the valve housing by a second spring, and 
 the second spring has larger bias force than the first spring. 
 
     
     
       11. The capacity control valve according to  claim 2 , further comprising a control pressure operated valve that includes a second spring arranged in a through hole which passes through the valve housing in an axial direction, and an operated valve element to be biased in a valve closing direction of the control pressure operated valve by the second spring, and that controls a communication between the control port and the space on the back surface side of the valve element. 
     
     
       12. The capacity control valve according to  claim 1 , wherein
 a communication between the control port and the space on the back surface side of the valve element is secured when an electromagnetic force is generated in the solenoid. 
 
     
     
       13. The capacity control valve according to  claim 12 , wherein
 the solenoid includes a coil, a plunger, a center post, and the first spring arranged between the plunger and the center post, 
 the plunger, the valve housing in which a through hole passing through in the axial direction is formed, and the center post, which is capable of closing an opening end of the through hole, cooperatively form a passage of the communication between the control port and the space on the back surface side of the valve element, and 
 the center post is movable toward the plunger by the electromagnetic force generated in the solenoid. 
 
     
     
       14. The capacity control valve according to  claim 13 , wherein
 the center post is pushed onto the valve housing by a second spring, and 
 the second spring has larger bias force than the first spring. 
 
     
     
       15. The capacity control valve according to  claim 1 , further comprising a control pressure operated valve that includes a second spring arranged in a through hole which passes through the valve housing in an axial direction, and an operated valve element to be biased in a valve closing direction of the control pressure operated valve by the second spring, and that controls a communication between the control port and the space on the back surface side of the valve element.